petersen



(No Model.) 5 Sheets-Sheet 1.

E. PETERSEN. TUBULAR BOILER.

No. 545,876. Patented Aug. 27,1895.

5 Sheets-Sheet 2.

(No Model.)

E. PETERSEN. TUBULAR BOILER.

No. 545,876. Patented Aug. 27,1895.

O O O O O (No Model.) 5Sheets-Sheet s. E

- E E. PETERSEN.

TUBULAR BOILER. No. 545,376. Patented Aug. 27,1895.

(No Model) 5 SheetsSheet 4. E. PETERSEN. TUBULAR BOILER Patented Aug.27, 1895.

E. PETERSEN,

( 5 Sheets-Sheefifi.

TUBULAR BOILER.

Patented Aug. 27, 1895.

UNITED STATES PATE T nron.

ERNEST PETERSEN, OF LONDON, ENGLAND.

TUBULAR BOILER.

SPECIFICATION forming part of Letters Patent No. 545,376, dated August27, 1895.

Applic i n fi d November 22,1894. Serial No. 529,615. (No model.)Patented in England December 7, 1893. 170.23,.577; in

Belgium May 4, 1894,1010. 109,769; in France May 12,1894, N0. 238,4=B4;in Italy February 7, 1895, LXXIV, 375; in Himgary February 11, 1895, No.2,150, andin Austria April 30,1895, N0. i=5 l,523.

To all whom it may concern.-

Be it known that I, ERNEST PETERSEN, a subject of the Emperor of Russia,residing at 5% Nelson Square, Blackfriars Road,London, in the county ofLondon, England, have invented certain new and useful Improvements inWater-Tube orTubulous Boilers, (for which I have obtained Letters Patentin Great Britain, dated December 7, 1893, No. 23,577; in Belgium, datedMayei, 1894,No. 109,769; in France, dated May 12, 1894, No. 238,484; inAustria, dated April 30, 1895, No. lo/1,523; in Hungary, dated February11, 1895, No. 2,150, and in Italy, dated February 7, 1895, No. LXXIV,375,) of which the following is a specification.

My invention relates to that class of water-- tube or tubulous boilersin which waterchambers arranged on each side of a fire-grate areconnected toa separate water and steam chamber above the fire-grate by anumber of watertubes of small diameter placed close together, so as tooffer a comparatively large amount of heating-surface to the flames andcombustion-gases which pass transversely through the interstices betweensuch tubes on their way to the uptake.

My present improvements have mainly for their object to obtain a verygreatly increased amount of heating-surface in the said watertnbes, ascompared with the constructions of such boilers as heretofore proposed,while very greatly reducing the number ofjoints required to be madebetween the water-tubes and the water-chambers, in addition to which agreat number of further advantagesare obtained thereby that willpresently be referred to.

The invention consists mainly in substiiuting for the separate smalltubes which in existing water-tube boilers connect the lowerwater-chambers to the upper water and steam chamber, groups of tubessomewhat similar to those described in the specification to my PatentNo. 475,150, but whose ends, instead of being secured in open cups, asthere described, are secured in closed cups or chambers, from one ofwhich a single tube extends down to the lower water-chamber of theboiler, while from the other a single short tube or neck passes throughthe upper steam and water chamber and is secured on the inside by ascrew-nut. By this arrangement the following advantages are obtainedover the existing constructions: In the latter the numberof separatetubes that can be grouped together on each side of the boiler is limitedby the distance which it is necessary to keep their ends apart wherethey are fixed to the upper and lower water-chambers, in order, on theone hand, to afford the requisite room for the screw-nuts or other meansof fining, and on the other hand to retain sufficient strength in thewalls of the Water-chambers to withstand the steam pressure.

With the improved constructions, as there is only one connecting-tube toevery group of say seven heating-tubes, there isno such limitation tothe closeness to which the tubes may be brought together, and as aresult more thandouble thenuinberofheating-tubes could be brought intothe space which the single tubes occupy in existing constructions.Again, with existing constructions a great proportion of the length ofmost of the watertubesnamely, from their connection with the lowerwater-chamber upward-is out of line of the draft of'the furnace, and istherefore useless for raising steam, constituting so much uselessexpenditure and dead weight.

With myimproved construction, there being only one connecting-tube toevery group of seven or more heating-tubes, such length of tubing thatis not efiective for raising steam is reduced to oneseventh or less ofthat of present constructions.

These are the main advantages of my improved construction, but, asbefore stated, there are numerous others, resulting from the generalconstruction of the boilers, which I will proceed to describe withreference to the accompanying drawings, in whicha Figure 1 shows a partend elevation and part transverse section; Fig. 2, a side view; Fig. 3,a plan; Fig. 4, a horizontal section on line X X, Fig. 1; Fig. 5, across-section on line Y Y; Fig. 6, a cross-section on line Z Z; Figs. 7,S, and 8*, enlarged sections of the cups and heating-tubes. Fig. 9showsa. part section at W XV. Fig. 10 shows an enlarged part section ofa modified form of the watertube connections. Fig. 11 shows a section ofa modified connection of the upper cups of the water-tubes. Figs. 12 and13 show sections of two arrangements of safety appliances for the lowerends of the water-tubes.

The boiler as here represented is arranged to have its furnace served atthe one end only. It may, however, be served from both ends. 4

A is the, fire-grate, which may be of any known construction. On eachside hereof is a tubular waterchamber B B, While at a suitable heightabove it is the water and steam chamber 0. The chambers B are connectedto the chamber 0 by means of groups of watertubes D, secured at each endin cups E E, of which the outer cups E are secured by a screwed joint totubes F, the lower ends of which are connected to thelower water-chamberB, while the inner cups E pass with their necks through the sides of thechamber 0, and are secured inside by means of screwnuts I and washers JJ. There are shown provided five horizontal rows of these tube groups oneach side of the furnace; but there may be any greater or less number ofsuch rows, the length of the tubes D between the cups E E being variedin the different rows, as shown, so that the whole of the same comewithin the effective draft of the fire, and it will be seen that eachrow is arranged more or less at right angles to the direction of thedraft, so that they are in the most effective position for taking up theheat from the flames.

Of the several rows, the two lower groups, which take up the greaterpart of the heat from the flames, are connected separately by theirconnecting-tubes F to the water-chambers B, while the upper three groupsare all connected to branches on one and the same connecting-tube F. Forthe attachment of the connectingtubes, the cylindrical waterchambers Bare formed with three longitudinal broad ribs B B .8, having passages atdistances apart corresponding to the distance apart of the successiveconnecting-tubes of each row, these ribs being in such positions thatthe one for the tubes F of the upper three rows is at top, while thosefor the tubes F of the two lower rows are arranged below, the object ofthis being to allow of the lastnamed connecting-tubes being formed witha considerable curvature, as shown, in order to allow of the freeexpansion and contraction of the tube groups, due to variations of temperature, without straining any of the connections.

Owing to the fact that there are only three rows of connecting-tubes tobe attached to the water-chambers B it will be seen that these can bemade of the smallest possible diameter consistent with an adequatesupply of water to all the heating-tubes, such water being suppliedthrough the large circulating-tubes V G that connect the ends of thelower waterchambers B with the water-space of the upper chamber O. Thewater-chambers B B are preferably cast either of gun-metal or'of softsteel.

The groups of tubesD are secured perfectly steam-tight in their cups EE, preferably by shrinking the latter (which are eitherof caststeel orwrought-iron) onto the ends of the tubes, this being effected by makingthe holes in the cups slightly smaller in diameter than the tubes, sothat when the cups are expanded by heating to a red heat the end of thetubes (cleaned and accurately turned) will just enter them. On coolingthe cups will then grasp the tubes as firmly as though they were of onepiece. The tubes may either be of steel or of copper or brass. Bypreference I make the two lower rows of steel and the upper rows ofcopper or brass. The cups may either be formed conical or they may bebellied as shown in the enlarged section at Fig. 7. They may also eitherbe circular for the reception of seven tubes, as at Fig. 8, or the fiatface may be made square with rounded corners, so as to afford room fornine tubes, the tapering part being kept conical at the smaller end, asat Fig. 8*. The tube groups are made to decrease in length in the upperrows as the hot combustion-gases, in becoming cooled considerably inpassing the lower rows, will decrease in volume, so that a less width isrequired for the passage leading to the uptake, the length of the tubesD being strictly limited to the effective heating-space of the furnace,this space being confined by sliding shield-plates H, which are slid inbetween the rows just beyond, the outerv cups E being made to rest uponthe connecting-tubes F and against the screw union-pieces E Thelongitudinal slits that are thus left between the contiguous plates arealso closed in by means of comb-like slotted plates H, that are slid inbetween the rows and are then dropped with their slots over theunion-pieces E It will be seen that these shield-plates protect not onlythe union-pieces E but also the tubes F from immediate contact with theflames and combustion-gases, and as the screwed joints that connect thecups E with the chamber O are inside the latter and always in contactwith water and steam there are absolutely no tube-joints that aredirectly in contact with the fire. The screwed joints within the chamber0 consist of a nut I, by preference of gun-metal, a recessed washer Jand a washer J of asbestos or other suitable material which by theaction of the coned inner surface of the washer J is forced not onlyagainst the surface of the chamber 0, but also against that of the neckof the cup E, so as to form a perfectly steam-tight joint, which is inaddition assured by the tight fit of the coned surface of the cupagainst the correspondingly-coned surface of the hole in 0.

As the upper rows of tube groups may be liable to have soot and ashesdeposited between them, I provide them with scrapers K, consisting ofplates having holes of such a screwed onto the neck.

size as to be capable of sliding freely backward and forward upon thetubes. These scrapers have rods K attached to them that extend outsidethe casing, so that by means thereof the scrapers can from time to timehe slid backward and forward upon the tubes in order to clear them ofsoot and ashes. It will be seen that should at any time one of the tubegroups become leaky or defective it can be readily removed by unscrewingthe connections with the water chambers B and O. In the case of thethree upper tube groups such removal is facilitated by forming theconnecting-tube F with an oblique flangejoint at F. arranged closelyside by side, so that the cups E E almost touch each other, as shown atthe enlarged section at Fig. 7. By this means the spaces between thecontiguous tube groups are only slightly larger than the spaces betweenthe individual tubes of each group, so that the flames andcombustion-gases will pass freely in between the latter and in becomingrepeatedly split up and mixed together in their passage a more completecombustion of the smoke and combustible gases will be attained. Aperforated shield X may be provided in the upper water and steam chamberover the openings of the cup E E, in order to prevent the water andsteam issuing from these to be projected with too much violence into thechamber, and thus to prevent primmg.

Fig. 10 shows a modified arrangement of the connection of the compoundtubes D with the lower water-chambers B. The two lower rows of thecompound tubes are connected to the curved branches F F of a tube F,fixed with a flange on a circular boss B on the upper part of thewater-tube '13, instead of each compound tube being connected by aseparate curved tube to the lower part of the tube B, as in the firstarrangement. By this means, while the curved branches F still allow ofthe free expansion and contraction of the compound. tubes withoutstraining the joints, the advantages are gained, first, that there isonly one joint with the tube B, instead of two, and,

secondly, this connection, being at the top instead of at the bottom ofB, there is no liability of its becoming choked with deposit. The bossesB of the tube B alternate with bosses B for tubes F connecting the threeupper rows of compound tubes, as in the first arrangement.

Provision may be made for preventing accidents and the stopping of theboiler on the bursting of one or more tubes of a compound tube, as shownat Figs. 11, 12, and 13. At Fig. 11 the neck of the upper cup E of thecompound tube is extended beyond the nutI and is formed with a circularedge, on which rests a valve a, guided by an open cap I), When theboiler is working, the valve (1 is kept open by the up ward flow ofwater and steam from E, but should one of the tubes D burst the clown-The tube groups of each row are ward flow caused bythe escape of waterand steam will cause the valve or to close down on its seat, and thusthe further escape be prevented. The escape is in like manner pre ventedat the lower end by adapting the branched tube F, Fig. 12, of the twolower rows, as also the tube F, Fig. 13, for the three upper rows tocontain a ball-valve c in a seat (Z, so that on the bursting of a tubethe increased speed of flow of water through F will carry up theball-valve 0, so as to close the branch through which the escape istaking place, as indicated by the dotted lines. One of the branches ismade sufficiently large for introducing the ballc through it, and alining e is then fixed to serve as a seat for the valve. If necessary,two ball-valves may be provided in the tube, one for each branch.

At Fig. 11 is shown a convenient mode of forming a water and steam tightjoint between the cups E and the chamber 0. It consists in introducing asmall copper ring fbetween the two, which, on the screwing up of the nutI, will constitute a steam and water tight packing, thus preventing thenecessity for producing an accurate fit between the coned surfaces ofthe cup and the chamber.

Although in the foregoing I have described the boiler as composed of twobottom waterchambers and a single upper water and steam chamber 0, it isobvious that there might be two or more upper water and steam chambersarranged side by side and communicating with each other.

The boiler is inclosed by a wrought-iron casing L, in which is aremovable ash-pit M, carrying the fire-grate. The ends of the casing areformed with doors L, through which access is gained to the tube groupsand for the introduction and removal of the shield-plates, and the tubesare also accessible at the sides, the plates L being hung at top bymeans of hooks onto tubular supports N and secured at bottom byfastenings 0, so that on releasing these the side plates can be removed.The tubular supports N, as also the uptake P, may be carried by trussedsaddle-shaped supports Q that rest upon the ends of the upper steam andwater chamber 0, this being in its turn carried by the returnwater-tubes G and lower water-chambers. B, that are carried on supportsR, forming the bottom of the boiler-casing. The back end of the latteris by preference constructed as shown in Figs. 5, 6, and 9-namely, as anon-conducting shield S, built up of sheet-iron S and S with anintermediate sheet of glass S packed with slag,wool,

or asbestos.

At the inner side of the shield S is a fire-- brick lining T, formingthe back of the furnace, and built up of a number of fire-clay blocks ofa shape to fit against the two side water-tubes and the under side ofthe steamchamber 0. These blocks are so formed that when placed inposition they are securely held together by key-blocks T, secured bybolts T as shown at Fig. 9.

IIO

Within this lining I of tube groups.

may be arranged a feed-water heater U, also.

formed of tube groups similar to those at D, through which thefeed-water is supplied either to the bottom of the upper steam and waterchamber 0 or to the lower water-chambers. The sides of thefurnace-chau1ber are also formed of fire-clay blocks T which extend upto the lower cups E of the first row The forced air supply isalso madeto pass through tube groups V,situated in the uptake, so as to be heatedon its way to the ash-pit through thepipesV. the steam passing off fromthe steam-chamber C may also be'made to pass through asuperheatercomposed of tube groups WV situated in the uptake. Both these and thetube groups V are provided with scrapers Y, operated by handles Y in thesame manner as those described in reference to the watertubes D.

The steam-chamber C may either be made plain, cylindrical, or withcorrugations between the tube groups, as shown at Fig. 7.

From What has been stated above it willbe seen that among otheradvantages the following most important ones will be obtained by myimproved construction of water-tube boilers as compared with water-tubeboilers of present construction.

First. A boiler constructed according to this invention for producing acertain steam power will be about two-thirds theweight of an ordinarywater-tube boiler having the same steam-producing power, and it willoccupy not more than two-thirds the space occupied by the latter. Thus aboiler of about nine feet nine inches height to the funnel and width ofeight feet eight inches will contain two hundred and four tube groups(including feed-heater and superheater) with fourteen hundred andtwenty-eight tubes of seveneig'nths of an inch diameter, and thesteamtubes will give an effective steam-producing surface of sevenhundred and fifty square feet, and the weight of the boiler charged withwater will only be about ten tons.

Second. It will require only about one-ninth. the number of holes in thewater and steam chambers, and consequently only about onesixth thenumber of joints.

Third. The joints are all out of reach of the fire or combustion-gases.

Fourth. Any tube group of any row can be removed and replaced in a veryshort space of time without disturbing the others, which is impossiblewith the ordinary constructions. This will also greatly facilitate theremoval of scale, as on taking out a tube group and beating it with ahammer the scale will at once drop off.

Fifth. The boiler can be easily taken to pieces and transported to anylocality where it can be rapidly set up and put to Work, no brickworkbeing required. Itis equally applicable as marine and land boilers.

Sixth. In ordinary water-tube boilers it is necessary to make thecombustion-chamber Lastly,

very small and low in order not to occupy to much room with the enormousnumber of water-tubes required. With my improved construction, owing tothe compact arrangement of the tubes, ample space can be given to thecombustion-chamber, resulting in a much greater development of heat andmore perfect combustion.

Seventh. Owing to the possibility of adapting scrapers to the tubegroups, which is im-.

possible with ordinary boilers, they can always be kept free from sootand ashes, and thusthe tube-surface always be maintained in the mosteffective condition for taking up heat and raising steam.

Having thus described the nature of my.

invention, and in what manner the same is to be performed, I claim 1. Inwater tube boilers, the combination with two lower water chamberssituated one on each side of the furnace grate, and a water and steamchamber above the grate, of groups of small water tubes connected ateach end to a closed tapering cup or box formed of one piece, the largeflat end being adapted to receive the said small tubes while the smallend has a threaded neck for connection to the other parts of the boiler,the one such box having its neck passed through a hole in the said upperwater and steam chamber and secured by a screw-nut on the inside, whilethe other cup or box is connected by its neck and a connecting tube tooneof the said lower water chambers of the boiler, there being severalrows of such tube groups arranged on each sideof the furnace,substantiallyas described.

2. A compound water tube for water-tube boilers consisting of a group oftubes of small diameter connected at each end to cups or boxes formed ofa single piece of a tapering shape, having at their large flat end aseries of holes for the reception of the ends of the tubes, and at thesmall end a threaded tubular neck for connection to other parts of theboiler the reduced portions of the cup being fitted in tapered openingsin the water and steam drum, and the threaded portion thereof beingentirely inclosed within said drum, substantially as described.

3. A box or cup for a compound water tube, consisting of a taperingreceptacle E formed of one piece and having a flat face at the largerend, with a series of holes adapted to receive the ends of the watertubes D and a threaded tubular extension at the smaller end, adapted tobe secured to the water and steam chambers of the boiler the reducedportions of the cups being fitted in tapered openings in the boxes E E,of which the cups E are fixed by pipes F to the chambers B while thecups E are fixed directly to the chamber 0, there being severallongitudinal rows of said compound tubes arranged one above the other,the reduced portions of the cups being fitted in tapered openings in thewater and steam drum, and the threaded portion thereof being entirelyinclosed within said drum substantially as described.

5. In water tube boilers, the combination with an upper water and steamchamber 0, and two lower water chambers B, of compound water tubescomposed of a number of small tubes D fixed at each end in tapering cupsor boxes E E of which the boxes E are fixed by tubes F to the chambers Bwhile the boxes E are fixed to the chamber Oby having their screwednecks passed through holes in the chamber and secured by internalscrew-nuts and washers, the coned surface of the boxes being made to fitwater-tight into the coned holes in the chamber 0, and the threadedportions of the necks being entirely inclosed within said drumsubstantially as described.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, this 8th day of November, A. D.1894:.

ERNEST PETERSEN. Witnesses:

CHAS. D. ABEL, .1110. P. M. MILLAR'D.

